SU1035462A1 - Method for determination of heat generation in material - Google Patents

Abstract

METHOD FOR DETERMINING HEAT FORMATION IN THE MATERIAL during operation of the structural element of the ways to measure, to increase the intensity of self-heating of the material under cyclic loading of samples of the material under conditions of hard deformation, so that, in order to improve the accuracy of determination heat generation in rubber elements of the tire design by approximating the test conditions to the actual loading, additionally statically testing a group of material samples and establishing the relationship between the deformation i and the strain 6, cyclic loading is carried out at different amplitudes of deformations; the dependences of the -intensity intensity q of self-heating on deformation, are established, and the dependence q is established according to the results of static testing. on voltage (T, and taking into account the above dependencies, judged (L about heat generation in the material.

Description

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o: o 1 1 The invention relates to the study of the mechanical properties of a material, and specifically to methods for determining heat generation in a material. It is known to determine the heat of formation in a material during operation and a structural element by measuring the intensity of the material self-heating under cyclic loading of material samples under conditions of severe deformation. Material samples are subjected to repeated compression with a predetermined strain amplitude and a constant frequency of exposure, and the material self-heating intensity is measured. TO The disadvantage of this method is the low accuracy of determining the heat of formation in rubber tire treads whose material is not subjected to hard deformation during operation. The purpose of the invention is to improve the accuracy of determining heat generation in rubber components of a tire by approaching the test conditions to the actual loading. The goal is achieved by the fact that according to the method of determining heat generation in a material during operation of a structural element by measuring the intensity of self-heating of a material under cyclic loading of material samples under conditions of severe deformation, a group of material samples is additionally statically tested and the relationship between the deformation and stress of the SU, cyclic loading is carried out at different amplitudes of deformations, the dependence of the intensity q of self-heating on d According to it, taking into account the results of static testing, the dependence of q on voltage is established (T, and taking into account these dependencies, heat generation in the material is judged. Figure 1 shows the dependences of the intensity of self-heating on the strain amplitude of two different materials; Fig. 2 - the dependence of stress on strain for the same materials; in Fig. 3, the dependence of the intensity of self-heating on the stress in the material. The method is carried out as follows. 2. 2 Samples of the studied material are cyclically loaded under conditions of known deformation at different amplitudes of deformations, the change in the temperature of the material as a result of its self-heating is measured, and the intensity q of self-heating is determined at the initial stage of the process of heat generation when there is a fraction of heat losses in the total heat sample balance is negligible. According to the results of cyclic tests, the dependence of the intensity q on the deformation ε is established. An example of such dependencies for two materials A and B is shown in FIG. 1. In addition, a group of samples of the material under investigation is statically tested for stretching or compression, and the dependence of non-strain in the material and the stress G arising in it is established. An example of such dependencies for materials A and B is shown in FIG. 2. Then, the dependence of the intensity q of self-heating on the voltage C is established. To do this, according to the results of cyclic tests for various values of q, the amplitudes of the deformations are determined according to the dependence shown in FIG. 1, and for the found values of 6, the values corresponding to them are established (Y according to the dependence shown in Fig. 2. An example of a change in the intensity of self-heating against voltage for materials A and B established according to the results of cyclic and static tests is shown in Fig. 3 Now, knowing stresses arising in real products (for example, in rubber treads of tires of large-sized machines, road-building devices, etc.), according to the test results, choose a material that is smaller than For example, based on the results of cyclic tests only (Fig. 1), it is possible to make a wrong conclusion that material B is more appropriate. However, taking into account the results of the static test (Fig. 3), it can be seen that when loading rubber tire treads with a load of less heat Material A. This improves the accuracy of heat generation in the material and makes it possible to choose 1035 (62 one or another material for the manufacture of structural elements of tires.

Claims (1)

METHOD FOR DETERMINING HEAT FORMATION IN MATERIAL during operation of a structural element by measuring the intensity of self-heating of a material under cyclic loading of material samples under severe deformation, due to the fact that, in order to increase accuracy determination of heat generation in the rubber elements of the tire structure by approximating the test conditions to actual loading, additionally statically using. try a group of samples of material · and establish the relationship between strain ί and stress 6, cyclic loading is carried out at different strain amplitudes, establish the dependences of self-heating intensity q on strain £. taking into account the indicated dependencies, heat generation in the material is judged.